In the art of electrochemical fuel cells, the chemical reactions between a single electrolyte and its related anode and cathode are different and are such that most effective and desired reaction, at both the anode and cathode, is unattainable. Accordingly, in most instances, the electrolytes for fuel cells are formulated to attain a compromise of chemical reaction as between the anodes and cathodes of the cells. For example, in fuel cells with aluminum anodes, to eliminate or reduce excessive corrosion of the aluminum and the formation of undesirable quantities of hydrogen gas and yet efficiently utilize the aluminum anode, the electrolytes are compounded with corrosion inhibitors to reduce corrosion of the aluminum to acceptable levels. With few exceptions, electrolytes which effectively attain the foregoing end are ineffective to establish and maintain most effective and efficient reaction at the cathodes of the cells. It has been determined that the above noted problem can be effectively eliminated by a fuel cell structure in which two different, but compatible, electrolytes are used. That is, a cell structure in which one electrolyte is provided to react with the anode and another which is provided to react with the cathode, whereby most effective and efficient reactions are attained at both the anode and cathode. It has been further determined that the effective use of two different electrolytes to attain the above noted end can be effected by establishing a cell structure with a cationic membrane in spaced relationship between the anode and the cathode and which establishes a fluid barrier between dissimilar anode and cathode electrolytes within the cell.
The ability to effectively use two different electrolytes in fuel cells, in the manner noted above, materially increases the range of materials that can be used as anode and cathode fuels and oftentimes notably increases the effectiveness and the efficient use of such fuels or materials. In particular, the use of certain gases, as cathode fuels, which heretofore could not be effectively and efficiently used as cathode fuels in fuel cells is made possible and highly practical.